This invention relates to an apparatus used to simultaneously position and support both the leg and foot of a patient during application of a cast, and more particularly the invention relates to an apparatus, usable in a sterile environment, that can be adjusted to position the supported leg and foot at any feasible orientation by movement of the leg and foot and maintain the selected leg/foot joint alignment during the time casting material is applied and allowed to set. The applied cast can be easily detached from the apparatus without structural degradation.
Human knee, ankle and foot joints permit a very wide range of devise positioning of the foot with respect to the leg. When set in casts to promote bone mending, however, it is necessary to select specific leg/foot joint orientations and then maintain the selected positioning while the cast material is both applied and allowed to set. The difficulties of adjusting leg/foot orientation and maintaining the selected positioning during casting are exasperated if the patient has additionally been or is treated surgically and is anesthetized. Accordingly, devices to adjustably position and support legs and feet during casting have been known for a long time. For example, U.S. Pat. No. 743,663, issued Nov. 10, 1903, describes a device for setting fractured legs during surgery. The described device is supposed to effect a linear stretching of the patient's leg to reposition fractured bones. Linear stretching is described as resulting from positioning a rod under the length of the leg and attaching an end of that first rod by a strap to the thigh of the patient. A second rod is then attached to a bandage buckled or laced to the foot. This second rod is further attached to the first rod with a threaded bolt structure so the second rod can pull the attached foot with respect to the leg as the threaded bolt structure is turned. Cast material is then supposed to be applied to the foot and leg while the foot is so pulled. After the cast is set, the first rod and other associated structures have to be removed through holes in the cast some of which must be bored and then later filled. Not addressed in any fashion because it cannot be in the U.S. Pat. No. 743,663 is how to orient a patient's leg/foot arrangement to different configurations other than a stretched one with the foot positioned in a stretched relationship to the leg and the sole of the foot oriented at an essentially ninety degree angle to the stretched longitudinal axis of the leg. Further restricting utility of the apparatus described in the U.S. Pat. No. 743,663 are the facts that after applied cast materials have set, it is necessary to remove rods, curved metal bars, and structural cross pieces from under the set cast through holes left in the cast or bored through the set cast. Unavoidably, such manipulations of a cast set on a patient's leg and foot risk further injury to the patient by removal of structures from under the cast, and also decrease the structural strength of the cast as a result, for example, of boring holes through the cast or applying the cast material so sizable that there are holes in the set cast. Attempting to later fill sizable holes in the cast or otherwise patch the cast can seal large openings needed to remove structural devices so as to prevent moisture and dirt from getting under the cast, but such repairs unavoidably cannot always restore the structural strength that a complete cast, without large bored or constructed openings, would have provided.
More recent attempts to design adjustable stands for positioning and supporting feet and legs to be cast have also failed to recognize and address the need to permit casting while supporting a foot and leg in such a manner that substantial openings in the cast are not required to remove sizable support stand structures. For example, U.S. Pat. No. 3,143,110, issued Mar. 1, 1962, describes a foot holder device for a cast table. The described foot holder device includes both a structure to support the heel area of a foot and a sole plate, identified for a preferred embodiment as being made of a flat metal plate, that is slidably attached to the heel support structure. According to the description provided in the U.S. Pat. No. 3,143,110, a cast is formed about a foot supported by such a foot holder device so that after the cast is set the sole plate is supposed to be slid out from the cast through a hole provided in the toe area and the heel support structure as an integral unit is supposed to be removed from an opening left in the cast as applied that extends about the entire heel area. In other words, the cast has to be formed so that the heel of the cast foot is not supported in the cast. As with the earlier patented device, the U.S. Pat. No. 3,143,110 admits in its disclosures that after the cast is set and the holder device is removed, additional cast material can be coated over the pare portions of the heel and toes of the foot. Such patching cannot restore the structural strength that a complete cast, without constructed openings, would have provided. Additionally, as with the earlier patent, the U.S. Pat. No. 3,143,110 describes the foot holder device as only providing a single fixed angle for the sole of the supported foot to the longitudinal axis of the leg.